What you may have to do is fiddle with the pot that controls the stepper motor current.
I bought a cheap cnc desktop thingy a while ago and when I first had it connected up none of the axis would move. A little fiddle with the pot got things going.
If there is any identification on the plug in driver boards, should be 3 boards the same, try searching. If not some close pics of the boards may help.

Cheers
Rob